rpcs3/Utilities/Semaphore.cpp
Ivan aafcf44581 Header optimizations (#1684)
Shouldn't break anything. I hope.
2016-04-27 01:27:24 +03:00

91 lines
1.4 KiB
C++

#include "Utilities/Semaphore.h"
#include <mutex>
#include <condition_variable>
struct benaphore::internal
{
std::mutex mutex;
std::size_t acq_order{};
std::size_t rel_order{};
std::condition_variable cond;
};
void benaphore::wait_hard()
{
initialize_once();
std::unique_lock<std::mutex> lock(m_data->mutex);
// Notify non-zero waiter queue size
if (m_value.exchange(-1) == 1)
{
// Return immediately (acquired)
m_value = 0;
return;
}
// Remember the order
const std::size_t order = ++m_data->acq_order;
// Wait for the appropriate rel_order (TODO)
while (m_data->rel_order < order)
{
m_data->cond.wait(lock);
}
if (order == m_data->acq_order && m_data->acq_order == m_data->rel_order)
{
// Cleaup
m_data->acq_order = 0;
m_data->rel_order = 0;
m_value.compare_and_swap(-1, 0);
}
}
void benaphore::post_hard()
{
initialize_once();
std::unique_lock<std::mutex> lock(m_data->mutex);
if (m_value.compare_and_swap(0, 1) != -1)
{
// Do nothing (released)
return;
}
if (m_data->acq_order == m_data->rel_order)
{
m_value = 1;
return;
}
// Awake one thread
m_data->rel_order += 1;
// Unlock and notify
lock.unlock();
m_data->cond.notify_one();
}
void benaphore::initialize_once()
{
if (UNLIKELY(!m_data))
{
auto ptr = new benaphore::internal;
if (!m_data.compare_and_swap_test(nullptr, ptr))
{
delete ptr;
}
}
}
benaphore::~benaphore()
{
delete m_data;
}